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Nucleobindin-derived peptides, nesfatin-1 [NESF-1] and nesfatin-1-like-peptide [NLP] have diverse roles in endocrine and metabolic regulation. While both peptides showed a stimulatory effect on the synthesis of proopiomelanocortin (POMC), the adrenocorticotropic hormone (ACTH) precursor in mouse corticotrophs, whether NESF-1 and NLP have any direct effect on glucocorticoid [GC] synthesis in the adrenal cortex remains unknown. The main aim of this study was to determine if NESF-1 and/or NLP act directly on adrenal cortex cells to regulate cortisol synthesis in vitro. Whether NLP injection affects stress-hormone gene expression in the adrenal gland and pituitary in vivo in mice was also assessed. In addition, cortisol synthetic pathway in Nucb1 knockout mice was studied. Human adrenal cortical [H295R] cells showed immunoreactivity for both NUCB1/NLP and NUCB2/NESF-1. NLP and NESF-1 decreased the abundance of steroidogenic enzyme mRNAs, and cortisol synthesis and release through the AC/PKA/CREB pathway in H295R cells. Similarly, intraperitoneal injection of NLP in mice decreased the expression of enzymes involved in glucocorticoid (GC) synthesis in the adrenal gland while increasing the expression of Pomc, Pcsk1 and Crhr1 in the pituitary. Moreover, the melanocortin 2 receptor (Mc2r) mRNA level was enhanced in the adrenal gland samples of NLP injected mice. However, the global genetic disruption in Nucb1 did not affect most steroidogenic enzyme mRNAs, and Pomc, Pcsk2 and Crhr1 mRNAs in mice adrenal gland and pituitary gland, respectively. Collectively, these data provide the first evidence for a direct inhibition of cortisol synthesis and secretion by NLP and NESF-1. NUCB peptides might still elicit a net stimulatory effect on GC synthesis and secretion through their positive effects on ACTH-MC2R pathway in the pituitary. [ABSTRACT FROM AUTHOR]

Background Evidence indicates that birth weight and neonatal nutrition have lifelong effects. Animal models are required to improve our understanding of these factors. Objectives We aimed to develop and validate a swine model of birth weight and neonatal undernutrition. Methods At birth, a total of 112 piglets were identified as low (LBW; 1.22 ± 0.28 kg SEM) or normal birth weight (NBW; 1.70 ± 0.27 kg). From day 3 to weaning (day 28), piglets received normal nutrition (NN) or restricted nutrition (RN) via intermittent suckling, where piglets were isolated from the sow for 6 h/d. After weaning, pigs were fed a common diet for 28 d. Body weight (BW) was determined for the duration of the study. On days 28 and 56, empty carcass, viscera, and individual organ weights were determined in 8 pigs/treatment. Results LBW pigs remained smaller than NBW pigs, regardless of nutrient restriction (P < 0.05). Within birth weight category, RN reduced BW by day 7 after birth, which was maintained until weaning (P < 0.05); however, at 7 d postweaning there was no difference in BW due to RN (P > 0.05). At weaning, empty carcass, viscera, heart, liver, and lung weights were lower in LBW than in NBW pigs, whereas empty carcass, heart, small intestine, liver, kidneys, lung, and spleen weights were lower in RN than in NN pigs (P < 0.05). Brain weight was highest in NBW-NN and lowest in NBW-RN, with LBW intermediate, regardless of nutrient restriction (P < 0.05). Postweaning, LBW had lower empty carcass, viscera, heart, stomach, large intestine, liver, and kidney weights than NBW, whereas RN had a higher small intestine weight than NN (P < 0.05). Conclusions Intermittent suckling is an effective means of inducing nutrient restriction in a swine model. [ABSTRACT FROM AUTHOR]

Heart disease is the leading cause of death in humans and evidence suggests early life growth-restriction increases heart disease risk in adulthood. Therefore, this study sought to investigate the effects of low birth weight (LBW) and postnatal restricted nutrition (RN) on cardiac function in neonatal pigs. We hypothesized that LBW and RN would reduce cardiac function in pigs but this effect would be reversed with refeeding. To investigate this hypothesis, pigs born weighing <1.5 kg were assigned LBW, and pigs born >1.5 kg were assigned normal birth weight (NBW). Half the LBW and NBW pigs underwent ~25% total nutrient restriction via intermittent suckling (assigned RN) for the first 4 wk post-farrowing. The other half of piglets were allowed unrestricted suckling access to the sow (assigned NN). At 28 d of age (weaning), pigs were weaned and provided ad libitum access to a standard diet. Echocardiographic, vascular ultrasound, and blood pressure (BP) measurements were performed on day 28 and again on day 56 to assess cardiovascular structure and function. A full factorial three-way ANOVA (NN vs. RN, LBW vs. NBW, male vs. female) was performed. Key findings include reduced diastolic BP (P = 0.0401) and passive ventricular filling (P = 0.0062) in RN pigs at 28 d but this was reversed after refeeding. LBW piglets have reduced cardiac output index (P = 0.0037) and diastolic and systolic wall thickness (P = 0.0293 and P = 0.0472) at 56 d. Therefore, cardiac dysfunction from RN is recovered with adequate refeeding while LBW programs irreversible cardiac dysfunction despite proper refeeding in neonatal pigs. [ABSTRACT FROM AUTHOR]